An overall objective of our research is to create a foundation science for understanding the contributions of cortical plasticity and learning to the origins of, and the expressions of human neurological disability, and to use that new understanding to guide remediation therapies. In this project, we shall study cortical plastic changes induced by repetitive, stereotyped, cognitively important movement exercises generating coincident afferent inputs that degrade the cortical representations of muscle and skin afferent information in the cortex. We shall further document the neurology of emergent repetitive strain injuries (RSI) including focal dystonias of the hand (Fdh) generated by this behavioral training, and relate training-generated de-differentiation of brain representations of movements and feedback sensory information controlling movements to the progression of sensorimotor dysfunction. We shall define the relationship of experience- induced changes in SI and MI to the onset and progression of pain and inflammation in the arm, and determine whether or not pain onset a) enables or amplifies, or b) could be triggered by dynamic, parralel cortical representational degradation. We shall determine whether induced plastic changes in motor and sensory cortical fields are posturally specific, which is signature feature of emergent focal dystonias. We shall determine whether or not and how postural strain might contribute to RSI/FDh genesis. Finally, we shall evaluate remediation training strategies in this primate model, to access behavioral strategies for redifferentiating cortical representations of sensory afferents and movements that have been degraded by RSI/FDh-inducing behaviors. This study should lead to a fundamental change in how we view cortical plasticity and learning contributions to chronic neurological disease, and could have a major impact on the development of more effective remediation therapies for this very large and growing patient group.